This does not specifically answer your questions but may be of interest.

According to an NAA document (134 Sqn Tour File) two Australians were flight commanders with 134 around this time. The digitised service file of J.E. Franks (A.403731) confirms he was ‘A’ Flt commander until posting out on 20 Jun 45. R.H. Cuthbertson (A.413355) was apparently the other (presumably ‘B’ Flt?), however his service file has not been made accessible as yet. Cuthbertson joined 134 during March 1945. Both it seems left the renumbered squadron soon after the change.

Incidentally there were another two RAAF with the new 131 Sqn RAF. F/Os J.M. Lock (A.404967) and W.C. Francis (A.404955) had seen prior service in the ME and volunteered for duty in the FE. Both were made F/Lts around mid 1945, however, not flight commanders.